Method of preparing copper-containing wood preserving compositions

ABSTRACT

The present invention relates to a method for producing copper ammonia solutions by reacting a cuprous oxide with ammonia, carbon dioxide and an oxidant. The resulting copper-containing solution can then be used to formulate a variety of wood preserving products.

The instant application claims priority to U.S. Provisional ApplicationSer. No. 62/553,173 filed on Sep. 1, 2017 which is hereby incorporatedby reference in its entirety. All patents, printed publications, andreferences cited herein are hereby incorporated by reference in theirentireties.

TECHNICAL FIELD OF INVENTION

The present invention relates to methods of preparing copper-containingaqueous solutions.

BACKGROUND OF THE INVENTION

Wood preserving compositions are well known for preserving wood andother cellulose-based materials, such as paper, particleboard, textiles,rope, etc., against organisms responsible for the destruction of wood,namely fungus and insects. Many conventional wood preservingcompositions comprise copper amine complexes. Copper amine complexeshave been used in the past because the copper when in such complexesbecome soluble in aqueous solutions. The copper in such copper aminecomplexes is obtained from a variety of copper-containing materials,such as copper scrap, cuprous oxide, copper carbonate, copper hydroxide,a variety of cuprous and cupric salts, and copper-containing ores. Theamine in such copper amine complexes is normally obtained from anaqueous solution of ammonia and ammonium salts, such as ammoniumcarbonate, and ammonium sulfate.

U.S. Patent Publication 2007/0207076 described producingmetal-containing amine solutions by reacting a metal or metal-containingcompound, in particular copper or a copper-containing compound, with anamine, carbon dioxide and an oxidizing agent. The resulting metal-aminesolution is disclosed as useful to formulate a variety of metal-basedwood preserving products.

Published Canadian Patent Application No. 2,262,186 A1 describes methodsfor dissolving copper metal comprising circulating an aqueous solutionmonoethanolamine through a bed of copper metal, and simultaneouslypassing a source of oxygen through the bed of copper metal; an apparatusfor dissolving copper metal comprising a receptacle for containingcopper metal, a receptacle for containing an aqueous solution ofmonoethanolamine, means for pumping the monoethanolamine from thereceptacle containing the monoethanolamine to the receptacle containingthe copper metal, and pressure means for providing air to the receptaclecontaining the copper metal; and a process for preserving wood whereinthe wood is infiltrated with gaseous carbon disulfide, and impregnatedwith an aqueous solution of copper ions and dlmethylamine.

U.S. Pat. No. 4,622,248 describes forming copper amine complexes bydissolving copper oxide in ammonia in the presence of ammoniumbicarbonate.

Some of the first experiments with ammonia and copper-containing orewere carried out at Federal Lead Company, Flat River, Mont., in theearly 1900's. The ore was leached by percolation with ammonia andammonium bicarbonate solutions to form various cupric-ammoniumcompounds. The copper-ammonia solution was separated from the ore andheated with steam to remove both the ammonia and carbon dioxide andprecipitate the copper as cupric oxide. The removed ammonia and carbondioxide may be collected and recycled.

U.S. Pat. No. 5,492,681 disclose processes to produce cupric oxidedissolving copper-containing materials with aqueous ammonia and anammonium salt in the presence of oxygen to form a cupric amine compound.Upon heating, the cupric amine compounds decompose to cupric oxide,ammonia and water.

There has been an unmet need for efficient methods of preparing solublecopper complexes suitable for the preparation of wood preservativecompositions. The methods of the present invention provide meet thisneed.

SUMMARY OF THE INVENTION

The present invention provides methods for producing copper-containingsolutions. In a preferred embodiment, cuprous oxide ammonia, carbondioxide and an oxidant are provided, combined to produce an aqueoussolution that promotes the dissolution of the copper.

The present invention provides a method for dissolving copper or acopper-containing material comprising the steps of mixing cuprous oxide,water, ammonia, carbon dioxide in an amount less than about 15% byweight, optionally a cationic surfactant, and an oxidant such that theaqueous solution contains between about 5 and about 12% by weightdissolved copper within 5, 3, 2 or 1 hours. In another embodiment, theaqueous solution contains about 6% dissolved copper within 5 minutes,about 6% dissolved copper within 10 minutes, about 8% dissolved copperwithin 10 minutes, about 8% dissolved copper within 20 minutes, about10% dissolved copper within 20 minutes, about 10% dissolved copperwithin 30 minutes, about 10% dissolved copper within 40 minutes, andabout 10% dissolved copper within 60 minutes. In another embodiment, themethods of the present invention provide average dissolution rates ofbetween 1 and 20%, 2 and 20%, 3 and 20%, 4 and 20% 5, and 20%, 6 and20%, 7 and 20%, 8 and 20%, 9 and 20%, 10 and 20%, 11 and 20%, 12 and20%, 13 and 20%, 14 and 20%, 15 and 20%, 16 and 20%, 17 and 20%, 18 and20%, 10 and 30%, 11 and 30%, 12 and 30%, 13 and 30%, 14 and 30%, 15 and30%, 16 and 30%, 17 and 30%, 18 and 30%, 19 and 30%, 20 and 30%, 21 and30%, 22 and 30%, 23 and 30%, 24 and 30%, and 25 and 30% by weight copperdissolved per hour. In another embodiment, the methods of the presentinvention provide average dissolution rates of about 1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20% by weight copperdissolved per hour. In yet another embodiment, the methods of thepresent invention provide average dissolution rates of between about 0.1and 1% per minute or between about 0.1 and 0.6%, 0.2 and 0.6%, 0.3 and0.6%, 0.4 and 0.6%, 0.1 and 0.5%, 0.2 and 0.5%, or 0.3 and 0.5% byweight copper dissolved per minute. In one embodiment, the term averagedissolution rate, as used herein, means the rate over any portion of thereaction. In another embodiment, the average dissolution rate refers tothe initial portion of the reaction, for example, between 0-5, 0-10,0-20, 0-30 or 0-60 minutes.

The present invention also provides a method for dissolving cuprousoxide comprising the steps of mixing the cuprous oxide, water, ammonia,carbon dioxide, optionally a cationic surfactant, and an oxidant suchthat the aqueous solution contains between about 5 and about 12% byweight dissolved copper within 5, 3, 2 or 1 hours. In anotherembodiment, the aqueous solution contains about 6% dissolved copperwithin 5 minutes, about 6% dissolved copper within 10 minutes, about 8%dissolved copper within 10 minutes, about 8% dissolved copper within 20minutes, about 10% dissolved copper within 20 minutes, about 10%dissolved copper within 30 minutes, about 10% dissolved copper within 40minutes, and about 10% dissolved copper within 60 minutes. In anotherembodiment, the methods of the present invention provide averagedissolution rates of between 1 and 20%, 2 and 20%, 3 and 20%, 4 and 20%5, and 20%, 6 and 20%, 7 and 20%, 8 and 20%, 9 and 20%, 10 and 20%, 11and 20%, 12 and 20%, 13 and 20%, 14 and 20%, 15 and 20%, 16 and 20%, 17and 20%, 18 and 20%, 10 and 30%, 11 and 30%, 12 and 30%, 13 and 30%, 14and 30%, 15 and 30%, 16 and 30%, 17 and 30%, 18 and 30%, 19 and 30%, 20and 30%, 21 and 30%, 22 and 30%, 23 and 30%, 24 and 30%, and 25 and 30%by weight copper dissolved per hour. In another embodiment, the methodsof the present invention provide average dissolution rates of about 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20%by weight copper dissolved per hour. In yet another embodiment, themethods of the present invention provide average dissolution rates ofbetween about 0.1 and 1% per minute or between about 0.1 and 0.6%, 0.2and 0.6%, 0.3 and 0.6%, 0.4 and 0.6%, 0.1 and 0.5%, 0.2 and 0.5%, or 0.3and 0.5% by weight copper dissolved per minute. In one embodiment, theterm average dissolution rate, as used herein, means the rate over anyportion of the reaction. In another embodiment, the average dissolutionrate refers to the initial portion of the reaction, for example, between0-5, 0-10, 0-20, 0-30 or 0-60 minutes.

The present invention also provides a method for dissolving cuprousoxide comprising the steps of mixing the cuprous oxide, water, ammonia,and carbon dioxide, optionally a cationic surfactant, and introducing anoxidant to the solution at an air at flow rate of between about 0.5 and100 standard cubic feet per hour (SCFH). In one embodiment, the oxidantis introduced at an air flow rate of between 0.5 and 10, 0.5 and 20, 0.5and 30, 0.5 and 40, 0.5 and 50, 1 and 5, 1 and 10, 1 and 20, 1 and 30, 1and 40, 1 and 50, 2 and 10, 2 and 20, 2 and 30, 2 and 40, 2 and 50, 5and 10, 5 and 20, 5 and 30, 5 and 40, 5 and 50, 10 and 20, 10 and 30, 10and 40, 10 and 50, 10 and 60, 10 and 70, 10 and 80, 10 and 90, 10 and100, 20 and 50, 20 and 60, 20 and 70, 20 and 80, 20 and 90, or 20 and100 SCFH.

The present invention also provides a method for dissolving copper or acopper-containing material comprising the steps of mixing cuprous oxide,water, ammonia, carbon dioxide, an oxidant and a cationic surfactant. Inone embodiment, the cationic surfactant is a quaternary ammoniumcompound. In one embodiment, the quaternary ammonium compound is presentin an amount sufficient to produce an average dissolution rate at least1.5-, 2-, 5-, or 10-fold of that rate observed in the absence of thequaternary ammonium compound. In another embodiment, the surfactant isin a concentration sufficient to produce a copper-amine solution at arate at least 50% greater than that observed in the absence of thesurfactant. In another embodiment, the cationic surfactant is present inan amount sufficient to substantially reduce any solid residue produceduring the reaction. In yet another embodiment, the cationic surfactantis present in an amount sufficient to produce substantially no visibleresidue during the reaction.

The present invention also provides a method for dissolving coppercomprising the steps of mixing cuprous oxide, water, between about 5 to25% by weight ammonia (by weight), carbon dioxide in an amount less thanabout 15% by weight, an oxidant and a quaternary ammonium compound suchthat the aqueous solution contains between about 5 and about 12% byweight dissolved copper within 5, 3, 2 or 1 hours. In anotherembodiment, the aqueous solution contains about 6% dissolved copperwithin 5 minutes, about 6% dissolved copper within 10 minutes, about 8%dissolved copper within 10 minutes, about 8% dissolved copper within 20minutes, about 10% dissolved copper within 20 minutes, about 10%dissolved copper within 30 minutes, about 10% dissolved copper within 40minutes, and about 10% dissolved copper within 60 minutes. In anotherembodiment, the methods of the present invention provide averagedissolution rates of between 1 and 20%, 2 and 20%, 3 and 20%, 4 and 20%5, and 20%, 6 and 20%, 7 and 20%, 8 and 20%, 9 and 20%, 10 and 20%, 11and 20%, 12 and 20%, 13 and 20%, 14 and 20%, 15 and 20%, 16 and 20%, 17and 20%, 18 and 20%, 10 and 30%, 11 and 30%, 12 and 30%, 13 and 30%, 14and 30%, 15 and 30%, 16 and 30%, 17 and 30%, 18 and 30%, 19 and 30%, 20and 30%, 21 and 30%, 22 and 30%, 23 and 30%, 24 and 30%, and 25 and 30%by weight copper dissolved per hour. In another embodiment, the methodsof the present invention provide average dissolution rates of about 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20%by weight copper dissolved per hour. In yet another embodiment, themethods of the present invention provide average dissolution rates ofbetween about 0.1 and 1% per minute or between about 0.1 and 0.6%, 0.2and 0.6%, 0.3 and 0.6%, 0.4 and 0.6%, 0.1 and 0.5%, 0.2 and 0.5%, or 0.3and 0.5% by weight copper dissolved per minute. In one embodiment, theterm average dissolution rate, as used herein, means the rate over anyportion of the reaction. In another embodiment, the average dissolutionrate refers to the initial portion of the reaction, for example, between0-5, 0-10, 0-20, 0-30 or 0-60 minutes.

The methods of the present invention provide dissolution rates where theaqueous solution contains between about 5 and about 12% by weightdissolved copper within 5, 3, 2 or 1 hours. In another embodiment, theaqueous solution contains about 6% dissolved copper within 5 minutes,about 6% dissolved copper within 10 minutes, about 8% dissolved copperwithin 10 minutes, about 8% dissolved copper within 20 minutes, about10% dissolved copper within 20 minutes, about 10% dissolved copperwithin 30 minutes, about 10% dissolved copper within 40 minutes, andabout 10% dissolved copper within 60 minutes. In another embodiment, themethods of the present invention provide average dissolution rates ofbetween 1 and 20%, 2 and 20%, 3 and 20%, 4 and 20% 5, and 20%, 6 and20%, 7 and 20%, 8 and 20%, 9 and 20%, 10 and 20%, 11 and 20%, 12 and20%, 13 and 20%, 14 and 20%, 15 and 20%, 16 and 20%, 17 and 20%, 18 and20%, 10 and 30%, 11 and 30%, 12 and 30%, 13 and 30%, 14 and 30%, 15 and30%, 16 and 30%, 17 and 30%, 18 and 30%, 19 and 30%, 20 and 30%, 21 and30%, 22 and 30%, 23 and 30%, 24 and 30%, and 25 and 30% by weight copperdissolved per hour. In another embodiment, the methods of the presentinvention provide average dissolution rates of about 1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20% by weight copperdissolved per hour. In yet another embodiment, the methods of thepresent invention provide average dissolution rates of between about 0.1and 1% per minute or between about 0.1 and 0.6%, 0.2 and 0.6%, 0.3 and0.6%, 0.4 and 0.6%, 0.1 and 0.5%, 0.2 and 0.5%, or 0.3 and 0.5% byweight copper dissolved per minute. In one embodiment, the term averagedissolution rate, as used herein, means the rate over any portion of thereaction. In another embodiment, the average dissolution rate refers tothe initial portion of the reaction, for example, between 0-5, 0-10,0-20, 0-30 or 0-60 minutes.

In one embodiment, the carbon dioxide is present in an amount less thanabout 15%, 10%, 5%, 4%, 3%, 2% or 1% by weight.

In certain embodiments of the invention, the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X⁻ is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodide, formate, acetate, propionate, acetate, propionate, andother alkyl carboxylates. In certain embodiments, the value of m is atleast 8 and at most 14, and the value of n is at least 8 and at most 14.In certain embodiments, the value of m is 10 or 12, the value of n is 10or 12, the value of a is 1, the value of b is 1. In certain embodimentsX⁻ is borate, chloride, propionate, carbonate, or bicarbonate. Incertain embodiments, the value of m is 10 and the value of n is 10. Incertain embodiments, the value of m is 12 and the value of n is 12.

In certain embodiments of the invention, the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X⁻ is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodide, formate, acetate, propionate, acetate, propionate, andother alkyl carboxylates. In certain embodiments, the value of m is atleast 8 and at most 14. In certain embodiments, the value of n is atleast 8 and at most 14. In certain embodiments, the value of a is 1, thevalue of b is 1. In certain embodiments X⁻ is borate, chloride,propionate, carbonate, or bicarbonate. In certain embodiments, the valueof m is 10 and the value of n is 10. In certain embodiments, the valueof m is 12 and the value of n is 12.

In certain embodiments of the invention, the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X⁻ is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodides, formate, acetate, propionate, and other alkylcarboxylates. In certain embodiments, the value of m, n is 10 or 12, thevalue of a is 1, the value of b is 1, and X⁻ is borate, chloride,propionate, carbonate, or bicarbonate.

In a more preferred embodiment, the quaternary ammonium compound isn-alkydimethyl benzyl ammonium chloride, alkyldimethylbenzylammoniumchloride, alkyldimethylbenzylammonium carbonate/bicarbonate,didecyldimethyl ammonium chloride, didecyldimethyl ammoniumcarbonate/bicarbonate, didodecyldimethyl ammonium chloride,didodecyldimethyl ammonium carbonate/bicarbonate,cocobis(2-hydroxyethyl) methylammonium chloride, anddidecylmethylpoly(oxyethyl)ammonium propionate.

Each of the methods of the present invention may also be practiced byintroducing the oxidant to the solution at a flow rate of between about0.5 and about 100 standard cubic feet per hour (SCFH). In oneembodiment, the oxidant flow rate is between about 0.5 and 5 SCFH. Inanother embodiment, the oxidant flow rate is between about 0.5 and about10 SCFH. In yet another embodiment, the oxidant is introduced at an airflow rate of between 0.5 and 10, 0.5 and 20, 0.5 and 30, 0.5 and 40, 0.5and 50, 1 and 5, 1 and 10, 1 and 20, 1 and 30, 1 and 40, 1 and 50, 2 and10, 2 and 20, 2 and 30, 2 and 40, 2 and 50, 5 and 10, 5 and 20, 5 and30, 5 and 40, 5 and 50, 10 and 20, 10 and 30, 10 and 40, 10 and 50, 10and 60, 10 and 70, 10 and 80, 10 and 90, 10 and 100, 20 and 50, 20 and60, 20 and 70, 20 and 80, 20 and 90, or 20 and 100 SCFH.

In the methods of the present invention, the cuprous oxide, water,ammonia and the oxidant are mixed in a single reaction chamber. In apreferred embodiment, the single reaction chamber is columnar. Inanother embodiment, the water, ammonia and the oxidant are mixed in afirst reaction chamber and the resulting solution is circulated throughcopper or a copper-containing material in a second reaction chamber. Inone embodiment, carbon dioxide is introduced either in the form of airor as carbon dioxide gas into the solution in the first reactionchamber. Alternatively, carbon dioxide is introduced either in the formof air or as carbon dioxide gas into the solution and cuprous oxide inthe second reaction chamber. In yet another embodiment, the methods ofthe present invention may be practiced by adding the carbon dioxide tothe solution, either in the first or second reaction chamber, afteraddition of the copper.

In the methods of the present invention, the solution contains betweenabout 5 to 25% by weight ammonia. Preferably, the solution containsbetween about 10 to 20% by weight ammonia. More preferably, the solutioncontains between about 8 to 15% by weight ammonia.

In the methods of the present invention, the oxidant is oxygen, air,ozone, or hydrogen peroxide.

Each of the methods of the present invention may also be practiced byadding a defoaming agent to the solution. In one embodiment, thedefoaming agent is a silicon polymer. In another embodiment, the siliconpolymer is polyoxylalkylene silicon.

Each of the methods of the present invention may also be practiced atambient temperature, for example room temperature, or by heating thesolution to between about 20 and about 100° C. Preferably, thetemperature is maintained between about 30° and about 80° C. Morepreferably, the temperature is maintained between about 40° and about70° C. Most preferably, the temperature is between about 50 and 60° C.

Each of the methods of the present invention may also be practiced byadding an a source of carbon dioxide selected from, for example,carbonic acid, dry ice, ammonium carbonate, ammonium bicarbonate andcarbon dioxide. Preferably, carbon dioxide is present in the solution inan amount less than about 15% by weight. In one embodiment, the carbondioxide is added to the solution prior to addition of the cuprous oxide.In another embodiment, the carbon dioxide is added to the solution afteraddition of the cuprous oxide. In another embodiment, the carbon dioxideis added to the solution during the addition of the cuprous oxide.

Each of the methods of the present invention may also be practiced byinitially adjusting the pH of the solution to between about 9 and 12.Preferably, the pH is initially adjusted to between about 10.5 and about11.5. In another embodiment, the pH of the solution is maintainedbetween about 10 and 12 by the addition of carbon dioxide. In apreferred embodiment, the pH of the reaction is maintained at about 10.5and about 11.5. In a more preferred embodiment, the pH of the reactionis maintained about pH 11.

Each of the methods of the present invention may also be practiced byadding an anti-foaming agent, stirring the solution, circulating thesolution or conducting the methods of the present invention at pressuregreater than 1 atmosphere.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. Production of copper ammonium carbonate according to Example 2.

FIG. 2. Production of copper ammonium carbonate according to Example 3.

FIG. 3. Production of copper ammonium carbonate according to Example 4.

FIG. 4. Production of copper ammonium carbonate according to Example 5.

FIG. 5. Production of copper ammonium carbonate according to Example 6.

FIG. 6. Production of copper ammonium carbonate according to Example 7.

DETAILED DESCRIPTION OF INVENTION

The present invention provides a method for the production of adissolved copper ammonia solution that efficiently produces the solutionat an expedited rate. For purposes of this application, the copperammonia solution is obtained by dissolving cuprous oxide that isnormally insoluble in water.

Carbon dioxide may be added prior to or after the addition of thecuprous oxide to the composition to adjust the pH of the mixture toabout 11.0. However the preferred addition order is prior to theaddition of the cuprous oxide. The process can be run without theaddition of carbon dioxide; however, the dissolution rate of the coppersource is reduced significantly. Sources of carbon dioxide include butare not limited to air, carbon dioxide (g), dry ice (s)(i.e. dry ice),carbonic acid, ammonium carbonate and ammonium bicarbonate.

Any source of oxygen can be used to oxidize copper in this process. Pureoxygen, however, is preferred. Air, ozone, and hydrogen peroxide arealso suitable sources of oxygen for use in this process providingstandard safety precautions are taken for using oxidants in the presenceof organic compounds.

The copper dissolution process could be conducted at ambient pressure.Alternatively the copper dissolution process could be conducted underpressure, such as less than 200 PSI. Preferably, the copper dissolutionprocess could be conducted at pressures less than 100 PSI, less than 50PSI, Less than 25 PSI and less than 10 PSI.

In certain embodiments of the invention, the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X− is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodide, formate, acetate, propionate, acetate, propionate, andother alkyl carboxylates. In certain embodiments, the value of m is atleast 8 and at most 14, and the value of n is at least 8 and at most 14.In certain embodiments, the value of m is 10 or 12, the value of n is 10or 12, the value of a is 1, the value of b is 1. In certain embodimentsX− is borate, chloride, propionate, carbonate, or bicarbonate. Incertain embodiments, the value of m is 10 and the value of n is 10. Incertain embodiments, the value of m is 12 and the value of n is 12.

In certain embodiments of the invention, the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X⁻ is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodide, formate, acetate, propionate, acetate, propionate, andother alkyl carboxylates. In certain embodiments, the value of m is atleast 8 and at most 14. In certain embodiments, the value of n is atleast 8 and at most 14. In certain embodiments, the value of a is 1, thevalue of b is 1. In certain embodiments X⁻ is borate, chloride,propionate, carbonate, or bicarbonate. In certain embodiments, the valueof m is 10 and the value of n is 10. In certain embodiments, the valueof m is 12 and the value of n is 12.

In certain embodiments of the invention, the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X⁻ is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodides, formate, acetate, propionate, and other alkylcarboxylates. In certain embodiments, the value of m, n is 10 or 12, thevalue of a is 1, the value of b is 1, and X⁻ is borate, chloride,propionate, carbonate, or bicarbonate.

In a more preferred embodiment, the quaternary ammonium compound isn-alkydimethyl benzyl ammonium chloride, alkyldimethylbenzylammoniumchloride, alkyldimethylbenzylammonium carbonate/bicarbonate,didecyldimethyl ammonium chloride, didecyldimethyl ammoniumcarbonate/bicarbonate, didodecyldimethyl ammonium chloride,didodecyldimethyl ammonium carbonate/bicarbonate,cocobis(2-hydroxyethyl) methylammonium chloride, anddidecylmethylpoly(oxyethyl)ammonium propionate. The resulting dissolvedcopper solution can be mixed with a variety of biocides such asfungicides and insecticides to produce a formulation suitable for thepreservation of wood and other cellulose-base materials. Typicalbiocides that can be used for this formulation are fungicides such asazoles, quaternary ammonium compounds, and various other conventionalinsecticides.

Another embodiment of the present invention is a method for preservingand/or waterproofing a wood substrate by contacting a wood substratewith the composition of the present invention. The composition may beapplied by any wood treating method known to one of ordinary skill inthe art including, but not limited to, brushing, dipping, soaking,vacuum impregnation (e.g. double vacuum technique), and pressuretreatment using various cycles.

Modifications and variations of the present invention for a process forthe production of aqueous copper amine solutions will be obvious tothose skilled in the art from the foregoing detailed description of theinvention. Such modifications and variations are intended to come withinthe scope of the appended claims.

EXAMPLES

The following Examples serve to further illustrate the present inventionand are not to be construed as limiting its scope in any way.

Example 1

A solution mixture of 771.4 g of water and 862.0 g of aqueous ammoniumhydroxide solution containing 29% ammonia was added to a beaker. Thesolution was mixed while a glass frit connected to a CO2 tank wassubmerged in the beaker and sparged into the solution. After thesparging of CO2 was complete, a charge of 181.8 g of cuprous oxidepowder was added to the beaker while mixing. A separate glass fritconnected to an oxygen line was submerged into the solution. Oxygen wasthen sparged into the solution while mixing. Solution samples wereperiodically taken during the reaction process to measure the coppercontent of the solution. After 3 hours of sparging oxygen into thesolution, a solution sample was taken and analyzed for Cu. The Cu wasfound to be low, about 4.0%, so more oxygen was sparged into thesolution to try to react the rest of the cuprous oxide. The reaction wascontinued for about 9 hours and the Cu content was analyzed atapproximately 4.5% which was still much lower than the theoretical valueof 8.0%. It was apparent much of the cuprous oxide was unreacted due tothe excess buildup of material on the walls of the beaker as well assolid material present in the beaker.

Example 2

A solution mixture of 771.4 g of water and 862.0 g of aqueous ammoniumhydroxide solution, containing 29% ammonia was added to a beaker. Thesolution was mixed while a glass frit connected to a CO2 tank wassubmerged in the beaker and sparged into the solution. Approximately120.0 g of CO2 was initially added to the solution, with the remaining40.0 g left out to be added after the reaction is complete for pHadjustment. The temperature of the solution after the addition of CO2was at about 50° C. Before the addition of cuprous oxide, 2.65 g ofantifoam and 1.0 g of alkyldimethylbenzyl ammonium chloride (ADBAC) wasadded to the solution while mixing. Approximately 181.8 g of cuprousoxide powder was added to the solution while mixing. Immediately afterthe addition of cuprous oxide, a glass frit connected to an oxygen linewas submerged into the solution. The sparging of oxygen was initiatedand was continued for a total of 3 hours. During the reaction, thetemperature was measured at about 60° C. Solution samples wereperiodically taken during the reaction process to measure the coppercontent of the solution. After the reaction was complete at 3 hours, theglass frit connected to the CO2 tank was re-submerged in the solutionand a final 38.0 g of CO2 was added.

The final Cu concentration was analyzed at about 8.31% and the reactionran much smoother than the previous batch with no residue left on thewall of the beaker. A graph depicting the copper results throughout thereaction are shown in the appendix as FIG. 1.

Example 3

A solution mixture of 465.2 g of water and 1077.6 g of aqueous ammoniumhydroxide solution, containing 29% ammonia, was added to a beaker. Thesolution was mixed while a glass frit connected to a CO2 tank wassubmerged in the beaker and sparged into the solution. Approximately190.0 g of CO2 was then added to the solution while mixing. Thetemperature of the solution after the addition of CO2 was at about 60°C. Before the addition of cuprous oxide, 2.50 g of antifoam and 1.22 gof alkyldimethylbenzyl ammonium chloride was added to the solutionmixing. Immediately after the addition of cuprous oxide, a glass fritconnected to an oxygen line was submerged into the solution. Thesparging of oxygen was initiated and was continued for approximately 3hours. About 90 minutes into the reaction, a large amount of foam beganto form in the beaker, so an additional 0.50 g of antifoam was added tothe solution while mixing. Solution samples were periodically takenduring the reaction process to measure the copper content of thesolution.

The final Cu concentration was analyzed at about 10.24%. A graphdepicting the copper results throughout the reaction are shown in theappendix as FIG. 2.

Example 4

A solution mixture of 771.4 g of water and 862.0 g of aqueous ammoniumhydroxide solution, containing 29% ammonia, was added to a beaker. Thesolution was mixed while a glass frit connected to a CO2 tank wassubmerged in the beaker and sparged into the solution. Approximately130.0 g of CO₂ was initially added to the solution, with the remaining31.0 g left out to be added after the reaction is complete for pHadjustment. Before the addition of cuprous oxide, 2.10 g of antifoam and1.5 g of cocobis(2-hydroxyethyl) methylammonium chloride was added tothe solution while mixing. Approximately 181.8 g of cuprous oxide powderwas added to the solution while mixing Immediately after the addition ofcuprous oxide, a glass frit connected to an oxygen line was submergedinto the solution. The sparging of oxygen was initiated and wascontinued for approximately 3 hours. Solution samples were periodicallytaken during the reaction process to measure the copper content of thesolution. After the reaction was complete at 3 hours, the glass fritconnected to the CO₂ tank was re-submerged in the solution and a final30.0 g of CO₂ was added.

The final Cu concentration was analyzed at about 8.14%. A graphdepicting the copper results throughout the reaction are shown in theappendix as FIG. 3.

Example 5

A solution mixture of 612.8 g of water and 958.0 g of aqueous ammoniumhydroxide solution, containing 29% ammonia, was added to a beaker. Thesolution was mixed while a glass frit connected to a CO₂ tank wassubmerged in the beaker and sparged into the solution. Approximately140.0 g of CO₂ was initially added to the solution, with the remaining30.0 g left out to be added after the reaction is complete for pHadjustment. Before the addition of cuprous oxide, 3.20 g of antifoam and1.6 g of cocobis(2-hydroxyethyl) methylammonium chloride was added tothe solution while mixing. Approximately 229.4 g of cuprous oxide wasadded to the solution while mixing. Immediately after the addition ofcuprous oxide, a glass frit connected to an oxygen line was submergedinto the solution. The sparging of oxygen was initiated and wascontinued for approximately 3 hours. Solution samples were periodicallytaken during the reaction process to measure the copper content of thesolution. After the reaction was complete at 3 hours, the glass fritconnected to the CO2 tank was re-submerged in the solution and a final30.0 g of CO₂ was added.

The final Cu concentration was analyzed at about 9.23%. A graphdepicting the copper results throughout the reaction are shown in theappendix as FIG. 4. After a few days of static stability, a large chuckof solid formed on the bottom of the jug.

Example 6

A solution mixture of 846.56 g of water, with the remaining 164.56 gleft out for final re-adjustment, and 958.0 g of aqueous ammoniumhydroxide solution, containing 29% ammonia, was added to a beaker. Thesolution was mixed while a glass frit connected to a CO2 tank wassubmerged in the beaker and sparged into the solution. Approximately150.0 g of CO2 was added to the solution, with the remaining 130.0 gleft out to be added after the reaction is complete for pH adjustment.Before the addition of cuprous oxide, 3.27 g of antifoam and 2.84 g ofcocobis(2-hydroxyethyl) methylammonium chloride was added to thesolution while mixing. Approximately 378.6 g of cuprous oxide was addedto the solution while mixing. Immediately after the addition of cuprousoxide, a glass fit connected to an oxygen line was submerged into thesolution. The sparging of oxygen was initiated and was continued forapproximately 3 hours. About 60 minutes into the reaction, some foambegan to form in the beaker, so an additional 1.72 g of antifoam wasadded to the solution while mixing. Solution samples were periodicallytaken during the reaction process to measure the copper content of thesolution.

The final Cu concentration was analyzed at about 10.41%. A graphdepicting the copper results throughout the reaction are shown in theappendix as FIG. 5. After a few days of static stability, a large chuckof solid formed on the bottom of the jug.

Example 7

A solution mixture of 682.8 g of water and 960.8 g of aqueous ammoniumhydroxide solution, containing 29% ammonia, was added to a beaker. Thesolution was mixed while a glass frit connected to a CO2 tank wassubmerged in the beaker and sparged into the solution. Approximately105.0 g of CO2 was then added to the solution while mixing. Before theaddition of cuprous oxide, 2.6 g of antifoam and 1.6 g ofcocobis(2-hydroxyethyl) methylammonium chloride was added to thesolution while mixing. Approximately 229.4 g of cuprous oxide was addedto the solution while mixing. Immediately after the addition of cuprousoxide, a glass frit connected to an oxygen line was submerged into thesolution. The sparging of oxygen was initiated and was continued forapproximately 3 hours. About 20 minutes into the reaction, some foambegan to form in the beaker, so an additional 0.4 g of antifoam wasadded to the solution while mixing. Solution samples were periodicallytaken during the reaction process to measure the copper content of thesolution.

The final Cu concentration was analyzed at about 10.66%. A graphdepicting the copper results throughout the reaction are shown in theappendix as FIG. 6. No solid formation appeared in the jug after a fewdays of static stability.

1-39. (canceled)
 40. A method for producing a copper ammonia solutioncomprising: forming a mixture comprising: water; cuprous oxide; anammonia containing compound, wherein the mixture comprises 5 to 25% byweight ammonia, based on the total weight of the mixture; a carbondioxide source; and an oxidant; and wherein the cuprous oxide reactswith the ammonia to dissolve the cuprous oxide and form a copper ammoniasolution; wherein the cuprous oxide dissolves at an average dissolutionrate of at least 1% by weight copper per hour, based on the total weightof the copper ammonia solution.
 41. The method of claim 40, wherein thecarbon dioxide source comprises gaseous carbon dioxide, dry ice,carbonic acid, ammonium carbonate, ammonium bicarbonate, or acombination thereof.
 42. The method of claim 40, further comprisingintroducing the carbon dioxide source into the mixture in an amountsufficient to maintain a pH of the mixture between 10 and
 12. 43. Themethod of claim 40, wherein the oxidant comprises oxygen, air, ozone,hydrogen peroxide, or a combination thereof.
 44. The method of claim 40,further comprising introducing the oxidant into the mixture at a flowrate of between 0.5 and 100 standard cubic feet per hour (SCFH).
 45. Themethod of claim 44, wherein the flow rate of the oxidant is between 0.5and 5 SCFH.
 46. The method of claim 40, wherein the mixture ismaintained at a temperature in a range of 20° C. and 100° C.
 47. Themethod of claim 46, wherein the mixture is maintained as a temperaturein range of 50° C. and 60° C.
 48. The method of claim 40, wherein themixture is maintained at a pressure of less than 200 psi.
 49. The methodof claim 40, wherein the mixture further comprises 0.125% to 0.250% byweight of a quaternary ammonium compound based on the total weight ofthe mixture.
 50. The method of claim 49, wherein the quaternary ammoniumcompound has a chemical structure comprising:

wherein the value of m is at least 1 and at most 20, the value of n isat least 1 and at most 20, the value of a is at least 1 and at most 5,the value of b is at least 1 and at most 5, and X− is an anion selectedfrom the group consisting of borate, chloride, carbonate, bicarbonate,bromide, iodide, formate, acetate, propionate, and other alkylcarboxylates.
 51. The method of claim 49, wherein the quaternaryammonium compound comprises n-alkydimethyl benzyl ammonium chloride,alkyldimethylbenzylammonium chloride, alkyldimethylbenzylammoniumcarbonate, alkyldimethylbenzylammonium bicarbonate, didecyldimethylammonium chloride, didecyldimethyl ammonium carbonate, didecyldimethylammonium bicarbonate, didodecyldimethyl ammonium chloride,didodecyldimethyl ammonium carbonate, didodecyldimethyl ammoniumbicarbonate, cocobis(2-hydroxyethyl) methylammonium chloride,didecylmethylpoly(oxyethyl)ammonium propionatem, or a combinationthereof.
 52. The method of claim 49, wherein the quaternary ammoniumcompound comprises (C12-C18) dimethylbenzylammonium chloride.
 53. Themethod of claim 49, wherein the value of m and n is 10 or 12, the valueof a is 1, the value of b is 1, and X− is borate, chloride, propionate,carbonate, or bicarbonate.
 54. The method of claim 40, wherein thecuprous oxide, the water, the ammonia, the oxidant and the cationicsurfactant are mixed in a single reaction chamber.
 55. The method ofclaim 54, wherein the single reaction chamber is columnar.
 56. Themethod of claim 40, wherein the cuprous oxide dissolves at an averagedissolution rate of at least 0.2% by weight copper per minute based onthe weight of the copper ammonia solution during the first 10 minutes ofthe reacting the cuprous oxide with the ammonia.
 57. A method forproducing a copper ammonia solution comprising: forming a mixturecomprising: cuprous oxide; water; an ammonia containing compound,wherein the mixture comprises 5 to 25% by weight ammonia based on thetotal weight of the mixture; and 0.125 and 0.250% by weight of aquaternary ammonium compound based on the total weight of the mixture;introducing an oxidant to the mixture at a flow rate in a range of 0.5and 100 standard cubic feet per hour (SCFH); introducing a carbondioxide source to the mixture in an amount sufficient to maintain a pHof the mixture in a range of 10 and 12; and wherein the cuprous oxidereacts with the ammonia to produce a copper ammonia solution.
 58. Themethod of claim 57, wherein the carbon dioxide source comprises gaseouscarbon dioxide, dry ice, carbonic acid, ammonium carbonate, ammoniumbicarbonate, or a combination thereof.
 59. The method of claim 57,wherein the oxidant comprises oxygen, air, ozone, hydrogen peroxide, ora combination thereof.